Marquise Golconda Diamond Ring, 8.03 carats. Photo M.S. Rau Antiques

Known as the "Ultimate Diamond," this ring boasts an extremely rare and highly important Internally Flawless Golconda diamond weighing an amazing 8.03 carats. This glorious marquise-cut diamond is certified by the Gemological Institute of America to be type IIa, meaning it is pure and lacking any trace of nitrogen, the element that gives diamonds color. It is, by all standards, one of the very finest diamonds in the world. This diamond is splendidly cut in a luxuriously sophisticated marquise and, because it is Internally Flawless, it literally glows. While all Golconda diamonds are quite rare, a large example such as this is truly a masterpiece of nature. This breathtaking gemstone is flanked by tapered white diamond baguettes totaling .72 carats graded E color and VS1 clarity. Set in platinum. Price: $1,485,000

Golconda diamonds are the purest of all diamonds, possessing a level of clarity, purity and transparency unrivaled by any other diamond. They are universally accepted as the finest diamonds in the world, and, because they hailed from only one mine in the ancient region of Golconda that ceased production hundreds of years ago, these perfect stones are exceptionally rare, with only a relative handful known to exist. Because they lack any trace of nitrogen, a D-color Golconda is at least two full shades whiter than any other diamond known.

M.S. Rau Antiques - www.rauantiques.com